What helped people of the Neolithic era domesticate plants? clearing the land to raise crops
having more people to work on farms
developing new religions and belief systems
trading with people from nearby settlements

Clearing the land to raise crops

Explanation:

During the process to clear the land, humans began to understand how to deal with plants, and which species are better adapted to that kind of land. Plus, while understanding how to plant and crops, humans also tried to create tools and techniques to obtain the better of the plantation.  A good example is the use of canals to control the water and to use it in the plantation, but especially how to organize each part of the plantation.

first, the romans stayed isolated because they had to defend their own territories from neighboring cities that were harassing them, like the etruscans. second, once the romans managed to defeat their neighbors, and started to expand their territory, they started to build roads and bridges. finally, now that the romans have covered their territory with roads functioning as highways, they could mobilize their legions faster to assemble larger military units in a specific place

well 1 they have there leader that controls them